The manufacture of timepiece trains having gears with no backlash is complex, since this involves finding compatibility between optimum torque transmission with the best possible yield on the one hand, and good shock resistance on the other hand.
The solution of a flexible toothing, with each tooth comprising a rigid portion and an elastic portion, satisfactorily answers the problem of energy transmission but is less satisfactory as regards the problem of shock resistance. This is all the more true given that these flexible toothings are generally designed to be made of micro-machinable material, silicon or similar material, via a “LIGA” or similar method. EP Patent Application No. 2 112 567 A1 in the name of Rolex discloses a gear with backlash compensation comprising a wheel with flexible, elastic portions manufactured in this way.